#!/usr/bin/env python
import json
import re

import html5lib
import mechanize
from lxml import html

from calibre.web.feeds.news import BasicNewsRecipe


def classes(classes):
    q = frozenset(classes.split(' '))
    return dict(attrs={
        'class': lambda x: x and frozenset(x.split()).intersection(q)})


def as_article(source, log):
    url = source['url']
    title = source['title']
    desc = ''
    if source.get('field_subtitle'):
        desc += source['field_subtitle']
    if source.get('field_display_authors'):
        desc += ' by ' + source['field_display_authors']
    log(title, url)
    return {'url': url, 'title': title, 'description': desc}


def get_issue_data(br, log, node_id='1126213', year='2020', volnum='99', issue_vol='5'):
    headers = {
        'Accept': 'application/json, text/plain, */*',
        'Content-Type': 'application/json;charset=UTF-8',
        'Origin': 'https://www.foreignaffairs.com',
        'Referer': 'https://www.foreignaffairs.com',
    }

    def make_query(**kwds):
        size = kwds.pop('size', 1)
        is_filter = kwds.pop('filter', None)
        if is_filter:
            q = {'filter': [{'terms': {k:v}} for k, v in kwds.items()]}
        else:
            q = {'must': [{'term': {k:v}} for k, v in kwds.items()]}
        return {
            'from': 0,
            'post_filter': {'bool': q},
            "_source": {
                "includes": [
                    "nid", 'path', 'title', 'field_subtitle', 'field_display_authors',
                    'fa_node_type_or_subtype',

                    'field_issue_sspecial_articles__nid',
                    'field_issue_sspecial_header'
                ]
            },
            "query": {
                "match_all": {}
            },
            'sort': [{'field_sequence': "asc"}, {'fa_normalized_date': "desc"}],
            "size": size,
        }

    def get_data(data):
        search_url = 'https://www.foreignaffairs.com/fa-search.php'
        req = mechanize.Request(url=search_url,
                                data=json.dumps(data),
                                headers=headers,
                                method='POST')
        res = br.open(req)
        data = json.loads(res.read())
        return data['hits']['hits']

    feeds = []
    issue_data = get_data(make_query(
        fa_node_type_or_subtype='Issue',
        field_issue_volume=issue_vol, field_issue_year=year,
        field_issue_volume_number=volnum
    ))[0]['_source']
    main_sec_title = issue_data['title'][0]
    main_sec_nids = issue_data['field_issue_sspecial_articles__nid']
    articles_data = get_data(make_query(nid=main_sec_nids, filter=True, size=len(main_sec_nids)))
    articles = []

    def as_article(source):
        title = source['title'][0]
        desc = ''
        fs = source.get('field_subtitle')
        if fs:
            desc = fs[0]
        aus = source.get('field_display_authors')
        if aus:
            desc += ' By ' + aus[0]
        url = 'https://www.foreignaffairs.com' + source['path'][0]
        return {'title': title, 'description': desc, 'url': url}

    log(main_sec_title)
    for entry in articles_data:
        source = entry['_source']
        articles.append(as_article(source))
        log('\t', articles[-1]['title'], articles[-1]['url'])
    feeds.append((main_sec_title, articles))

    articles_data = get_data(make_query(field_issue__nid=node_id, size=50))
    ans = {}
    for entry in articles_data:
        source = entry['_source']
        section = source['fa_node_type_or_subtype'][0]
        ans.setdefault(section, []).append(as_article(source))
    for sectitle in sorted(ans):
        articles = ans[sectitle]
        log(sectitle)
        if articles:
            for art in articles:
                log('\t', art['title'], art['url'])
            feeds.append((sectitle, articles))

    return feeds


class ForeignAffairsRecipe(BasicNewsRecipe):
    title = u'Foreign Affairs'
    __author__ = 'Kovid Goyal'
    language = 'en'
    publisher = u'Council on Foreign Relations'
    category = u'USA, Foreign Affairs'
    description = u'The leading forum for serious discussion of American foreign policy and international affairs.'

    no_stylesheets = True
    remove_javascript = True
    needs_subscription = 'optional'

    INDEX = 'https://www.foreignaffairs.com/magazine'

    keep_only_tags = [
        classes('article-header article-body article-lead-image article-body-text'),
    ]
    remove_tags = [
        classes('loading-indicator paywall article-footer')
    ]

    conversion_options = {'comments': description, 'tags': category, 'language': 'en',
                          'publisher': publisher}

    def parse_index(self):
        soup = self.index_to_soup(self.INDEX)
        # get dates
        date = re.split(r'\s\|\s', self.tag_to_string(
            soup.head.title.string))[0]
        self.title = "Foreign Affairs ({})".format(date)
        self.timefmt = u' [%s]' % date
        link = soup.find('link', rel='revision', href=True)['href']
        year, volnum, issue_vol = link.split('/')[-3:]
        self.cover_url = (soup.find('img', {'class': 'subscribe-callout-image'})['data-src']
                          .split("|", 1)[0].replace('issue_small_1x', 'issue_large_2x'))

        cls = soup.find('body')['class']
        if isinstance(cls, (list, tuple)):
            cls = ' '.join(cls)
        node_id = re.search(r'\bpage-node-(\d+)\b', cls).group(1)
        br = self.cloned_browser
        feeds = get_issue_data(br, self.log, node_id, year, volnum, issue_vol)
        return feeds

    def clean_fa_html(self, root):
        for svg in tuple(root.iter('{*}svg')):
            svg.getparent().remove(svg)
        for meta in tuple(root.iter('{*}meta')):
            meta.getparent().remove(meta)
        return root

    def preprocess_raw_html(self, raw_html, url):
        root = html5lib.parse(raw_html, treebuilder='lxml',
                              namespaceHTMLElements=False).getroot()
        self.clean_fa_html(root)
        return html.tostring(root, encoding='unicode')

    def preprocess_html(self, soup):
        for attr in ('ng-src', 'data-blazy', 'data-src'):
            for img in soup.findAll('img', attrs={attr: True}):
                img['src'] = img[attr]
        return soup

    def get_browser(self):

        def select_form(form):
            return form.attrs.get('id', None) == 'fa-user-login-form'

        br = BasicNewsRecipe.get_browser(self)
        if self.username is not None and self.password is not None:
            br.open('https://www.foreignaffairs.com/user/login')
            br.select_form(predicate=select_form)
            br.form['name'] = self.username
            br.form['pass'] = self.password
            br.submit()
        return br
